The invention concerns a lock, especially for doors or windows, wherein two latches each swinging about a pivot pin are mounted on one component, with their mutually facing ends engaging from opposite directions and from behind an undercut surface of a locking bolt mounted on the other component, the locking bolt having a cross-sectionally conical or wedge shaped tip by means of which the two latches can be forced apart against an opposing spring force.
In a known lock of this kind, the latches are pivotable about a common axis, both latches being in the shape of a double-arm lever at one end of which are mounted the latch segments engaging from the rear the undercut surface of the locking bolt and at the other end of which is mounted the spring compressing the latches.
This known design suffers from the drawback that the known lock can easily be opened from the outside provided that a tool be inserted between the two oppositely moving latches which then are spread apart. Once the latches are apart, the door or window is opened effortlessly.